use crate::history::{annotated_transcript_from_history, partial_findings_from_history};
use crate::models::WRITER_MODEL;
use crate::progress::{SUMMARIZE_EMOJI, Spinner};
use rig::client::AgentClientExt;
use rig::completion::{Message, Prompt};
use rig::providers::ollama;

/// Agentic alternative to the plain programmatic extraction in `history`:
/// hands the annotated transcript to a fresh model call and asks it to
/// reconstruct the same footnote-style findings dump the researcher would
/// have written itself, had it not run out of turns. This can dedupe
/// repeated URLs and restore correct `[n]` citation numbering in a way
/// string concatenation can't — but it's a model call like any other, so on
/// an empty transcript or a failure it falls back to
/// `partial_findings_from_history` rather than letting a second turn-budget
/// problem take down the one recovery path that's supposed to be
/// bulletproof.
#[tracing::instrument(skip(client, chat_history), fields(gen_ai.agent.name = "history-summarizer"))]
pub(crate) async fn summarize_partial_history(
    client: &ollama::Client,
    topic: &str,
    chat_history: &[Message],
    show_progress: bool,
) -> String {
    let transcript = annotated_transcript_from_history(chat_history);

    if transcript.is_empty() {
        tracing::warn!("no usable transcript to summarize; skipping summarizer pass");
        return partial_findings_from_history(chat_history);
    }

    let summarizer = client
        .agent(WRITER_MODEL)
        .name("history-summarizer")
        .preamble(
            "You are reconstructing research notes from a research session that was cut off \
             before the researcher could write its own summary. You'll be given a raw transcript \
             of tool calls (searches run, pages fetched), their results, and any interim comments \
             the researcher made. Turn this into a footnote-style findings dump: write each fact \
             the transcript actually supports, followed by a bracketed number like [1], then end \
             with a 'Sources' section mapping each number to its exact URL, one per line. Reuse \
             the same number for a URL that appears more than once. Do not invent facts beyond \
             what the transcript shows, and note explicitly where it looks thin or cuts off \
             mid-investigation.",
        )
        .build();

    let spinner = Spinner::start(
        show_progress,
        format!("{SUMMARIZE_EMOJI} Reconstructing partial findings..."),
    );
    let result = summarizer
        .prompt(format!(
            "Topic: {topic}\n\nPartial research transcript:\n{transcript}"
        ))
        .await;
    drop(spinner);

    match result {
        Ok(findings) => {
            tracing::info!(findings = %findings, "summarizer reconstructed partial findings");
            findings
        }
        Err(error) => {
            tracing::warn!(%error, "summarizer agent failed; falling back to programmatic extraction");
            partial_findings_from_history(chat_history)
        }
    }
}